Resistant hypertension improved after 3 months by measuring drug levels to identify non-adherence

Abstract

\n \n \n Identification of non-adherence to antihypertensive drugs is crucial to improve resistant hypertension (RH). For this therapeutic drug monitoring is the most reliable method.\n \n \n \n The primary objective of this analysis is to determine whether drug levels measured with a dried blood spot (DBS) method combined with personalized feedback leads to a decrease in prevalence of RH after 3 months due to an increase in adherence.\n \n \n \n This is a multi-centre single-blinded randomized controlled trial (RHYME-RCT, NL6736). Patients went to an eligibility visit, where DBS sampling and a 24-hour ambulatory blood pressure measurement (ABPM) was performed simultaneously. Patients with a daytime systolic blood pressure (SBP) >135 and/or diastolic blood pressure (DBP) >85 mmHg were randomized to standard treatment (control) or intervention. The intervention was performed by the treating physician and included information on drug levels and a personalized feedback conversation based on a feedback tool. The follow-up period was one year and included visits at 3, 6 and 12 months after the eligibility visit. At each visit an ABPM and DBS were performed.\n \n \n \n A total of 53 patients (mean age of 59±11 years, 78.7% male) with at least three months of follow-up were included. The prevalence of RH decreased from 100% in both arms to 75.0% in the intervention arm (p=0.014, n=24) and 58.6% in the control arm (p=0.001, n=29). No improvements were seen in adherence rates over time. Furthermore, no significant differences were found after three months between the two groups in the degree of RH (p=0.214), SBP (p=0.551) or adherence (p=0.746).\n \n \n \n Measuring blood pressure and drug levels led to a decrease in the prevalence of RH. However, this improvement could not be linked to the actual intervention or improvement of adherence.\n \n \n \n Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ZonMW\n